Class 2 ~ Chapter 1

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Class 2 ~ Chapter 1
CSE 1340
Introduction to Computing Concepts
Class 2
Class 2 ~ Chapter 1
Review of course requirements:

Homework due Tuesday at beginning of
class-- no lates accepted

Programming assignments due during lab
hour or at the latest, 5pm the next day

Student’s responsibility to have work
turned in on-time or early. Programs and
their associated files must be uploaded to
Blackboard by the due date/time
Review of course requirements:
Class 2 ~ Chapter 1

Review of course requirements:
– Incentives for coming to class lecture
on Tuesdays and Thursdays
• Unannounced quizzes
• Unannounced fun logical quizzes and
bonus opportunities given for getting back
points lost on turned in homework
assignment
for that week
• Interactive Class notes distributed
Review of course requirements:
Class 2 ~ Chapter 1

Must enroll in a lab
 Lab sessions are mandatory
 Pop Quizzes cannot be made up
 Homework cannot be made up
 Programs can be turned in late BUT
only 1 day late; no late points assessed
 Make-up exams only given if
documented excuse has been
submitted BEFORE exam
Communication
Office hours
 via email:
Class 2 ~ Chapter 1

– Please identify yourself

Blackboard address
– http://courses.smu.edu (use your 8 digit smu
id for your userid and password)
Synchronization of passwords
Class 2 ~ Chapter 1

You can change your password in
Blackboard by going to your homepage
and clicking on “change password” in the
upper right-hand corner of the window.
Class 02 objectives
Class 2 ~ Chapter 1


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List the basic components of a computer system
Understand what a Computer Program is
List the Programming Life-Cycle Phases
Describe the characteristics of Java
Explain the uses of Java and identify types of Java
programs.
Computer Systems: Hardware and Software
Class 2 ~ Chapter 1

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Hardware --- the equipment
Software --- programs that run the equipment
Computer Components-Hardware
Class 2 ~ Chapter 1
Peripherals
Input Device
Central Processing Unit ( CPU )
Control Unit
Arithmetic Logic Unit
Output Device
Secondary
(Auxiliary)
Storage
Device
Memory Unit ( RAM & Registers )
Class 2 ~ Chapter 1
Memory Unit

is an ordered sequence of storage cells, each
capable of holding a piece of information

each cell has its own unique address

the information held can be input data, computed
values, or your program instructions.
Central Processing Unit
Class 2 ~ Chapter 1

has 2 components to execute program instructions
–
Arithmetic/Logic Unit performs arithmetic
operations, and makes logical comparisons.
–
Control Unit controls the order in which your
program instructions are executed.
Peripherals
Class 2 ~ Chapter 1

are input, output, or auxiliary storage devices attached
to a computer
–
Input Devices include keyboard and mouse.
–
Output Devices include printers, video display,
LCD screens.
–
Auxiliary/Secondary Storage Devices include disk
drives, scanners, CD-ROM and DVD-ROM drives,
modems, sound cards, speakers, and digital
cameras.
WHAT IS A PROGRAM?
Class 2 ~ Chapter 1

A program is a step-by-step series of
instructions for a computer
 Computer programming is the process of
writing these instructions
 Programmers, or developers, design and
write programs using a programming
language or development tool
 Java is a programming language that
provides the structure for efficient and
economical programs
Class 2 ~ Chapter 1
A SET OF INSTRUCTIONS
1. Display a message on the screen asking “How
many hours did you work?”
2. Wait for the user to enter the hours. Once the user
enter the hours, store it in memory
3. Display a message on the screen that asks “How
much do you get paid per hour?”
4. Wait for the user to enter the rate of pay. Once
the user enters the rate, store it in memory
5. Multiply hours by rate and store the result in
memory as gross pay
Page 7
6. Display the gross pay
Class 2 ~ Chapter 1
Inside the Program
PROCESSING
INPUT
OUTPUT
number
System.out.print(sum);
=keyboard.nextInt();
sum = sum + number;
The Programming Process
Class 2 ~ Chapter 1

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Analyze the requirements
– Precisely define what problem is to be
solved
Design the solution
– flowchart
– pseudocode
Validate the design
Implement the design
– Code the program
Test (debug) the solution (compile/run)
– Syntax errors
– Logical errors
Document the program
Class 2 ~ Chapter 1
Program Development Cycle
Phase 1 – Analyze the Requirements
Verify that the requirements are clear
and complete
 Evaluate the problem to determine
that it is solvable using a program
 List the required input and output
data
 Determine whether the input data is
available for testing
Class 2 ~ Chapter 1

Phase 1 – Analyze the Requirements
Ensure that a solution, or algorithm,
can be developed with the
information provided in the
requirements
 Verify the user interface
specifications
Class 2 ~ Chapter 1

Requirements
Document
Class 2 ~ Chapter 1
p. 13
Phase 2 – Design the Solution
Develop a logical model that
illustrates the sequence of steps you
will take to solve the problem
 Use design tools such as
storyboards, class diagrams,
flowcharts, and pseudocode to
outline the logic of the program
Class 2 ~ Chapter 1

Phase 2 – Design the Solution
Class 2 ~ Chapter 1

Storyboards are sketches of the user
interface
Phase 2 – Design the Solution
Flowcharts graphically represent the
logic used to develop an algorithm
 Control structures allow the
programmer to specify the code that
will execute only if a condition is met
 Flowcharts use pseudocode,
English, or mathematical notation
inside symbols to represent the
steps of a solution
Class 2 ~ Chapter 1

Flowcharting
symbols
Class 2 ~ Chapter 1
p. 17
Class 2 ~ Chapter 1
Phase 2 – Design the Solution
Class 2 ~ Chapter 1

Pseudocode is an English
representation of how the program
code should be written
Phase 3 – Validate the Design
The programmer steps through the
solution with test data
 The user agrees that the program
design solves the problem put forth
in the requirements
 The user verifies that the initial
requirements document contains all
necessary requirements
Class 2 ~ Chapter 1

Phase 4 – Implement the Design
Write the code that translates the
design into a program
 Create the user interface
 Create comments within the code
that explains the purpose of the code
 Unit testing
Class 2 ~ Chapter 1

– Test the code as it is written

Test related code
Class 2 ~ Chapter 1
Phase 4 – Implement the Design
Phase 5 – Test the Solution
Create a test plan with test cases of
sample input data and expected
output
 Perform integration testing to ensure
that components interact correctly
 Test boundary values
 Document any problems
Class 2 ~ Chapter 1

– If results are unsatisfactory, a new
iteration of the development cycle
begins
Phase 6 – Document the Solution
Requirements documents, program
design documents, user interface
documents, and documentation of
the code
 Test cases and proof of successful
completion of testing
 Program code should be archived
electronically
Class 2 ~ Chapter 1

Programming languages
Class 2 ~ Chapter 1

A special language used to write
computer instructions consisting of
– Key Words
• Words that have a special meaning
• Can only be used for their inteded
purpose.
– Programmer-Defined Symbols
• Words or names defined by the
programmer
Class 2 ~ Chapter 1
– Operators
• Operators perform operations on one
or more operands(a piece of data)
– Punctuation
• Punctuation characters that mark the
beginning of a statement, or separate
items in a list
– Syntax
• Rules that must be followed when
constructing a program
Class 2 ~ Chapter 1
Conclusion of Class 2
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